1. Field of the Invention
The present invention relates to a semiconductor booster circuit for stepping up voltage to substantially twice the power supply voltage, and to a step-up power supply device equipped with the semiconductor booster circuit.
2. Description of the Related Art
Data storage devices such as EEPROM (Electrically Erasable Programmable ROM) and flash memory are currently used in various data processing devices. FeRAM (Ferroelectric Random Access Memory) is also being investigated for use in these data storage devices. However, the power supply voltage of a typical data processing device is 3.0 V, and the voltage necessary for writing and erasing data on a FeRAM is substantially twice this voltage. Therefore, a booster circuit is typically used to double the voltage, and a booster circuit constituted by semiconductor elements is one type of such a booster circuit.
However, a semiconductor booster circuit of the prior art suffers from a disadvantage that in order to step up the power supply voltage to, for example, substantially twice the original voltage, it requires transistors having the breakdown voltage for this doubled voltage, decreasing the productivity of such circuits.